Mucinous adenocarcinoma of the renal pelvis associated with transitional cell carcinoma in the renal pelvis and the bladder

We report a case of mucinous adenocarcinoma of the renal pelvis associated with bladder carcinoma in situ (CIS). Transitional cell carcinoma (TCC) of the renal pelvis and CIS were also observed adjacent to the adenocarcinoma. Immunohistochemical assessment of the pelvic adenocarcinoma revealed positive expressions for mucin, epithelial membrane antigen, cytokeratin 7, cytokeratin 19 and carcinoembryonal antigen, but not vimentin or chromogranin. Based on the histopathological examinations, the adenocarcinoma of the renal pelvis in the present case may have a similar biological nature to conventional TCC and probably originated by development of pre-existing TCC of the renal pelvis.

CD2-associated protein in human urogenital system and in adult kidney tumours

We studied expression of CD2-associated protein (CD2AP) in human urogenital system and in adult kidney tumours. In the cortex of normal kidney, CD2AP was expressed in all types of tubules and in the glomeruli. Labelling was more intense in cytokeratin 7- and in Tamm-Horsfall-positive tubules than in proximal tubules. In the medulla, expression was observed in the collecting ducts. Urothelium and the epithelium of prostatic acini, seminal vesicles, seminiferous tubules, epididymal ducts, Fallopian tube, endometrium and endocervix as well as granulosa cells showed moderate to strong CD2AP positivity. In syncytiotrophoblast, the expression was weaker than in cytotrophoblast. Endometrial stroma was negative, but decidualised stroma was weakly positive. Clear cell renal cell carcinoma (RCC) (n=63) showed a weak expression. Type-I papillary RCCs (n=4) and papillary adenomas (n=3) were negative. The epithelium lining the cysts in multilocular cystic RCCs (n=3) and in cystic nephroma (n=1) was strongly positive. Chromophobe RCCs (n=2), oncocytomas (n=3) and urothelial carcinomas (n=2) were moderately positive. The results show that CD2AP displays a specific expression pattern in human urogenital organs and that distinct expression is shown in several types of kidney tumours but not in type-I papillary RCCs or in papillary adenomas.

Inhibition of Ki-67 in a renal cell carcinoma severe combined immunodeficiency disease mouse model is associated with induction of apoptosis and tumour growth inhibition

OBJECTIVE

To evaluate the effects of suppressing the expression of Ki-67 (expressed in proliferating cells) by antisense oligonucleotides (asON) directed against Ki-67 (which specifically inhibit the proliferation of tumour cells and tumour growth in cell culture and in subcutaneous murine tumour models) on the growth, cell viability and angiogenic activity of a preclinical renal cell carcinoma (RCC) severe combined immunodeficiency disease (SCID) mouse model.

MATERIALS AND METHODS

Human RCC cells (SK-RC-35) were incubated with asON and control ON in the presence of a cationic lipid in monolayer cell culture. To test Ki-67 as a target for antitumour therapy in more complex models, asON were administered to three-dimensional RCC (SK-RC-35) spheroid cultures and to SCID mice bearing subcutaneous SK-RC-35 xenografts. For animal studies, 1 x 10(6) SK-RC-35 cells were implanted subcutaneously. Subsequently, asON or ON were injected intraperitoneally daily for 14 days at 10 mg/kg/day. Tumour size, weight and status of metastasis were documented daily and after death, respectively. The number of apoptotic cells, Ki-67-positive cells and the microvessel density in tumour sections was determined immunohistochemically. Quantitative reverse transcription-polymerase chain reaction of Ki-67 mRNA was also assessed for the tumours.

RESULTS

Treatment of RCC cells with asON resulted in a specific inhibition of cell growth in monolayer and spheroid cell culture. Systemic administration of Ki-67-directed asON significantly decreased tumour growth (P = 0.009) in SCID mice. Immunohistochemical staining of tumour specimens showed stronger inhibition of Ki-67-positive cells in asON-treated tumours (mean 27.8%) than in controls (mean 42.5-57%). Furthermore, there were about twice as many apoptotic cells after asON treatment. There was no significant difference among treatment groups for microvessel density.

CONCLUSION

These results indicate that Ki-67 represents a suitable antiproliferative target, and that asON are a potent agent inhibiting tumour growth and apoptosis, but not tumour vascularization, in human RCC.

The pT1a and pT1b category subdivision in renal cell carcinoma: is it reflected by differences in tumour biology?

OBJECTIVE

To assess systematically the possible differences in pathology between pT1a and pT1b renal cell carcinomas (RCCs), as the sixth edition of the Tumour-Nodes-Metastasis (TNM) system implemented a subdivision of category pT1 into pT1a (<4 cm) and pT1b (4-7 cm), based on clinical outcome analysis and the approach to therapy.

PATIENTS AND METHODS

Conventional histopathology and immunohistochemical expression of several biomarkers were analysed in 66 patients with pT1a and 29 with pT1b RCCs, using a tissue microarray technique.

RESULTS

After 2 years of follow-up, none of the 66 patients with pT1a and three of the 29 with pT1b tumours developed progressive disease. The tumour was grade 3 in four (6%) pT1a and 11 (38%) pT1b RCCs. Immunohistochemically, pT1a RCCs were characterized by strong expression of p27 (79%), bcl-2 (67%), MUC1 (87%), insulin-like growth factor (IGF)-I (71%) and CD10 (88%), as well as moderate expression of IGF-I receptor (43%) and low expression of epidermal growth factor receptor (EGFR, 20%). During progression to category pT1b, expression of p27 significantly decreased (54%) and EGFR expression increased (38%). Moreover, membranous staining patterns of MUC1 and CD10 changed from apical to circumferential in clear cell RCCs. p53 (pT1a 23%, pT1b 28%), E-cadherin (10% and 17%), MIB-1 (1.2% and 1.5%) and Skp2 (2% and none) expression seemed to be of minor importance.

CONCLUSION

This is the first study to show that the subdivision of category pT1 implemented in the latest issue of the TNM system is reflected by differences in conventional histopathology and expression of biomarkers.

Kit (CD117) immunoreactivity is rare in renal cell and upper urinary tract transitional cell carcinomas

OBJECTIVE

To investigate the presence of Kit (CD117), a transmembrane tyrosinase-kinase receptor, in primary and metastatic renal cell carcinomas (RCCs) and upper urinary tract transitional cell carcinomas (TCCs).

MATERIALS AND METHODS

In human neoplasia, overexpression of Kit has been related to cell proliferation, differentiation, adhesion and control of apoptosis. If present, Kit may provide a suitable target for tumour therapy. Formalin-fixed and paraffin-embedded specimens of 180 primary and 58 metastatic RCCs and 54 upper urinary tract TCCs were immunostained for Kit (CD117) using a tissue microarray technique.

RESULTS

In RCCs, immunoreactivity for CD117 was detected in only two of 23 (9%) chromophobe tumours, whereas all 137 conventional and 20 papillary subtypes, and metastatic RCC tissues, lacked CD117 immunoreactivity. In TCCs, CD117 expression of <10% cancer cells was found in two of 53 (4%) cases. Stromal mast cells served as a positive control and showed specific immunostaining.

CONCLUSION

Kit immunoreactivity is infrequent in both RCCs and upper urinary tract TCCs. Thus, routine screening of tumour tissues for Kit by immunohistochemistry appears to be cost-ineffective and cannot be recommended. Moreover, the lack of substantial Kit immunoreactivity in both primary and metastatic carcinomas does not provide a rationale to investigate imatinib mesylate therapy in clinical trials including patients with advanced disease.

Lipomatous meningioma of the brain harboring metastatic renal-cell carcinoma: a case report

A 70-year-old woman presented with mild left hemiparesis and intermittent global headache. Magnetic resonance imaging showed a 6 x 6 x 6-cm tumor in the right frontal lobe, and abdominal computed tomography revealed a 8 x 8 x 7-cm mass lesion in the left kidney. Magnetic resonance imaging showed that the brain tumor consisted of a central hyperintense cystic component and an outer hypointense component. The patient underwent total surgical excision of the intracranial mass. Histological and immunohistochemical examination showed that the lesion was a lipomatous meningioma harboring metastatic renal-cell carcinoma. Both of these tumors are rare. The magnetic resonance imaging findings are indicative of but not specific to meningioma harboring metastatic tumor.

[The expression of hypoxia inducible factor-1,2 alpha in sporadic clear cell renal cell carcinoma and their relationships to the mutations of von Hippel-Lindau gene]

OBJECTIVE

To evaluate the expression of hypoxia inducible factor (HIF)-1alpha, 2alpha in sporadic clear cell renal cell carcinoma and their relationships to the mutations of von Hippel-Lindau (VHL) gene.

METHODS

Mutations of VHL gene, expression of HIF-1alpha and 2alpha were detected by polymerase chain reaction (PCR), direct DNA sequencing and immunohistochemistry in 77 cases of Chinese sporadic clear cell renal cell carcinoma (CCRCC). The stage was pT(1)N(0)M(0)in 55 patients (71%), pT(2)N(0)M(0) in 7 patients (9%), pT(3)N(0)M(0) in 14 patients (18%), and pT(4)N(0)M(0) in 1 patient (1%). The classification according to the tumor nuclear grading system showed 15 carcinomas (19%) of tumor nuclear grade 1, 56 (73%) of tumor nuclear grade 2 and 6 (8%) of tumor nuclear grade 3.

RESULTS

None of the VHL gene mutations were found in all the normal tissue specimens. VHL gene mutations were detected in 40 (52%) cases of CCRCC. The positive rate of HIF-2alpha (81%) was higher than that of HIF-1alpha (66%) (chi(2) = 23.310, P < 0.01); The positive rate of HIF-1alpha and HIF-2alpha in the cases of mutations (98% and 93% respectively) was higher than that of them in non-mutations (32% and 68% respectively) (chi(2) = 36.386, 7.617, P < 0.01); The correlation between HIF-1alpha and VHL gene mutations was closer than that between HIF-2alpha and VHL gene mutations (partial correlation coefficiency was 4.481 and 2.027 respectively, P < 0.01). The expression of HIF-1alpha and 2alpha in different pathological grade and stage of CCRCC showed no significant difference (P > 0.05).

CONCLUSIONS

Our study suggests that VHL gene mutations are frequent in sporadic CCRCC, and the high expression of HIF-1alpha and 2alpha are found in the group of VHL mutations. However, we have not found significant correlation between the expression of HIF-1alpha and 2alpha and pathological grade and stage of CCRCC in our study.

Chromophobe renal cell carcinoma with microcystic and adenomatous arrangement and pigmentation—a diagnostic pitfall. Morphological, immunohistochemical, ultrastructural and molecular genetic report of 20 cases

We present clinical, morphological, immunohistochemical, ultrastructural and molecular genetic features of 20 cases of a peculiar form of chromophobe renal cell carcinoma (CRCC) with morphology differing from that of conventional CRCC. Microscopically, the typical features of the tumors were microcystic arrangement and formation of adenomatous structures. Microcystic areas were composed of smaller eosinophilic and bigger pale cells having cytological appearance typical of conventional CRCC. Cytological features of the adenomatous structures were mostly different from those of conventional CRCC. They had a typical columnar arrangement with nuclei positioned at the base of the glandular structures and a small amount of a deeply eosinophilic cytoplasm often endowed with brush border facing the lumen of the glands. In addition, all the tumors showed a brown pigmentation. The pigmentation was located mostly extracellularly, where it formed pools of heavy deposits. Microscopic calcifications present in all cases formed psammoma bodies or else the calcifications were more extensive and amorphous in shape. Ultrastructurally, the cells showed features characteristic of CRCC: typical cytoplasmic vesicles were 100-700 nm in size and mitochondria had tubulovesicular, lamellar or circular cristae. Some tumor cells contained dark, variously sized electron-dense pigment granules. Neither melanosomes nor membrane-bound neurosecretory granules were seen. Using fluorescence in-situ hybridization probes for chromosomes 1, 2, 6, 10, 13, 17 and 21, the tumors revealed massive loss of tested chromosomes typical for conventional CRCC. Monosomy of chromosomes 1, 2, 6, 10, 13 and 21 was found in 100, 36, 91, 82, 82, 82 and 64% of cases, respectively. None of the cases showed mutation of exons 9, 11, 13 and 17 of the c-kit gene. The important feature of pigmented microcystic chromophobe renal cell carcinoma is a relatively benign biological behavior and the absence of distant metastases and sarcomatoid transformation.

Inhibition of Nox-4 activity by plumbagin, a plant-derived bioactive naphthoquinone

NAD(P)H oxidase contributes to the pathogenesis of cancer and cardiovascular diseases such as hypertension, atherosclerosis, restenosis, cardiac hypertrophy and heart failure. Plumbagin, a plant-derived naphthoquinone, has been shown to exert anticarcinogenic and anti-atherosclerosis effects in animals. However, the molecular mechanisms underlying these effects remain unknown. It is possible that the beneficial effect of plumbagin is due to the inhibition of NAD(P)H oxidase. Human embryonic kidney 293 (HEK293) and brain tumour LN229 cells express mainly Nox-4, a renal NAD(P)H oxidase. We have examined the effect of plumbagin on Nox-4 activity in HEK293 and LN229 cells using lucigenin-dependent chemiluminescence assay. Plumbagin inhibited the activity of Nox-4 in a time- and dose-dependent manner in HEK293 and LN229 cells. Production of superoxide in HEK293 cells was inhibited by diphenyleneiodonium (DPI), a NAD(P)H oxidase inhibitor. The superoxide production in HEK293 cells was NADPH- and NADH-dependent indicating that the superoxide was generated by a NAD(P)H oxidase in HEK293 cells, but not by the redox-cycling of lucigenin. Furthermore, plumbagin inhibited the superoxide production in Nox-4 transfected COS-7 cells. These results indicated that plumbagin directly interacted with Nox-4 and inhibited its activity.

Immunohistochemical analysis of hSNF5/INI1 distinguishes renal and extra-renal malignant rhabdoid tumors from other pediatric soft tissue tumors

Malignant rhabdoid tumor (MRT) is a highly aggressive neoplasm that occasionally demonstrates phenotypic overlap with other soft tissue malignancies. Molecular genetic analysis of MRT frequently demonstrates deletion or mutation of the hSNF5/INI1 gene, with corresponding reduced expression at the protein level. INI1 immunohistochemistry was performed to determine the utility of this method in assessing loss of INI1 expression in rhabdoid tumors. Twenty-seven MRTs with molecular analysis (19 renal, 8 extra-renal) were evaluated. Seventeen additional MRT (10 renal, 7 extra-renal) without INI1 molecular analysis were also analyzed. Loss of INI1 expression was observed in the tumor cells in all 44 cases. To determine the specificity of this assay, a variety of 45 pediatric soft tissue tumors, some of which occasionally display rhabdoid differentiation, were investigated. These included Ewing's sarcoma, Wilms' tumor, desmoplastic small round cell tumor, clear cell sarcoma, congenital mesoblastic nephroma, synovial sarcoma, undifferentiated sarcoma, rhabdomyosarcoma, and epithelioid sarcoma. Positive nuclear staining was found in all nonrhabdoid tumors examined. Of interest, synovial and epithelioid sarcomas exhibited variable and/or focal staining. INI1 antibody immunohistochemistry is useful in confirming the histologic diagnosis of renal or extra-renal rhabdoid tumor, especially for cases with indeterminate histologic features, equivocal immunophenotypic profiles, or uninformative molecular studies.

Human kidney injury molecule-1 is a tissue and urinary tumor marker of renal cell carcinoma

Human kidney injury molecule-1 (hKIM-1) is a type 1 transmembrane protein that is not detectable in normal kidney tissue but is expressed at high levels in human and rodent kidneys with dedifferentiated proximal tubule epithelial cells after ischemic or toxic injury. Therefore, it was hypothesized that renal tumors express hKIM-1 and release this protein into the urine. Forty renal cell carcinoma (RCC) and 484 nonrenal tumors were analyzed by immunohistochemistry for expression of hKIM-1 (group 1). Urine samples before nephrectomy and nephrectomy tissue samples were collected from an additional 42 patients with renal tumors, from 30 normal control subjects, and also from 10 patients with prostate carcinoma (group 2). In five additional patients with RCC, urine was collected before and after nephrectomy (group 3). Tissue was examined for expression of hKIM-1, and cell-free urine supernatants were analyzed for hKIM-1 by ELISA. Urinary hKIM-1 was normalized to the urinary creatinine concentration (U(Cr)). Expression of hKIM-1 was present in 32 tissue sections (91%) of 35 clear cell RCC (group 1). In group 2, the normalized urinary hKIM-1 levels were significantly higher in patients with clear cell RCC (0.39 +/- 0.08 ng/mg U(Cr); n = 21), compared with levels in patients with prostate carcinoma (0.12 +/- 0.03 ng/mg U(Cr); P < 0.02; n = 10), or normal control subjects (0.05 +/- 0.01 ng/mg U(Cr); P < 0.005; n = 30). Tissue sections from 28 (82%) of 34 primary RCC stained positively for the expression of hKIM-1. In all patients with a detectable prenephrectomy urinary hKIM-1 level, there was either complete disappearance or marked reduction after nephrectomy (group 3). In conclusion, the cleaved ectodomain of hKIM-1 can be detected in the urine of patients with RCC and may serve as a new biomarker for early detection of RCC.

Pediatric renal carcinoma associated with Xp11.2 translocations/TFE3 gene fusions and clinicopathologic associations

Renal cell carcinomas (RCCs) are rare in children and studies of their subtypes and clinicopathologic associations are limited to small series. We identified 8 patients with RCC treated at our institution between 1981 and 2003, reviewed their clinicopathologic features, cytogenetics findings, and evaluated the status of TFE3 expression by immunohistochemistry and numerical chromosomal alterations by interphase fluorescent in situ hybridization on paraffin-embedded tissue. These 8 patients (5 female and 3 male) had diploidy, and 5 had morphologic features compatible with the recently described RCC associated with Xp11.2 translocations/TFE3 gene fusions and demonstrated nuclear labeling for TFE3 protein by immunohistochemistry. The translocation was confirmed in 2 of these 5 patients by conventional cytogenetics. One case was a high-grade nonpapillary RCC and the other was compatible with type 2 papillary RCC. Four patients showed at least 1 chromosomal gain including trisomy 7 and/or trisomy 17. None of the tumors from male patients showed evidence of loss of the Y chromosome, but 2 patients showed numerical abnormalities of X chromosome +add(X). Two patients had sickle cell disease, and 1 of these also had stage IV-S neuroblastoma. This study suggests that many cases of RCC in children reported under the terms "papillary" and "clear cell" likely represent Xp11.2 translocation/TFE3 gene fusion-associated RCC. It also emphasizes the unusual associations of RCC with neuroblastoma and sickle cell hemoglobinopathy, which need further study.

Erythropoietin-producing renal cell carcinoma arising from autosomal dominant polycystic kidney disease

Erythropoietin (EPO)-producing renal cell carcinomas (RCC) in patients with chronic renal failure secondary to autosomal dominant polycystic kidney disease (ADPKD) has not previously been reported. We report a case of EPO-producing RCC associated with ADPKD in a 66-year-old woman, and discuss the clinical and radiological findings.

Pretargeting with bispecific anti-renal cell carcinoma x anti-DTPA(In) antibody in 3 RCC models

We have developed an efficient pretargeting strategy for renal cell carcinoma (RCC) based on a biologically produced bispecific monoclonal antibody (bs-mAb). Tumor targeting with this 2-step pretargeting strategy in the NU-12 mouse RCC model was very efficient compared with other pretargeting strategies, possibly due to unique characteristics of the NU-12 tumor used in our studies. Here we describe the bs-mAb G250xDTIn-1 pretargeting strategy in 3 different RCC nude mouse models.

METHODS

Three different human RCC xenografts in nude mice (NU-12, SK-RC-1, and SK-RC-52 tumors) were pretargeted with 100 pmol bs-mAb G250xDTIn-1. Three days after administration of the bs-mAb, mice were injected intravenously with 4 pmol 111In-labeled bivalent peptide, diDTPA-FKYK (DTPA is diethylenetriaminepentaacetic acid). At 1, 4, 24, 48, and 72 h after injection of the radiolabeled peptide, the biodistribution of the radiolabel was determined. The 3 RCC tumors were characterized in vivo and in vitro for G250 antigen expression, vessel density, vascular volume, and vascular permeability and by targeting with 111In-/125I-labeled cG250 mAb.

RESULTS

Using the pretargeting strategy, relatively high uptake of the radiolabel was observed in all 3 tumor models (maximum uptake: SK-RC-1 [278 +/- 130 %ID/g (percentage injected dose per gram), 1 h after injection] > NU-12 [93 +/- 41 %ID/g, 72 h after injection] > SK-RC-52 [54 +/- 9 %ID/g, 4 h after injection]). Remarkably, uptake of the radiolabel in the tumor did not correlate with G250 antigen expression. The kinetics of the radiolabel in the tumor varied largely in the 3 RCC tumors: SK-RC-1 and SK-RC-52 tumors showed a washout of the 111In label from the tumor with time: only 30% of the radiolabel was retained in the tumor 3 d after injection, whereas the 111In label was fully retained in NU-12 tumors. Physiologic characteristics (vessel density, vascular volume, and vascular permeability) of the tumors may explain these differences.

CONCLUSION

G250 antigen-expressing tumors can be pretargeted very efficiently with the bs-mAb G250xDTIn-1. There was no correlation between G250 antigen expression and uptake of the radiolabel in the tumor using the pretargeting strategy or with directly labeled mAbs. Therefore, these studies show that physiologic characteristics of the tumor, such as vascular permeability, play a significant role in pretargeting.

Inhibition of angiogenic activity of renal carcinoma by an antisense oligonucleotide targeting fibroblast growth factor-2

BACKGROUND

Fibroblast growth factor-2 (FGF-2) induces angiogenesis, critical for the growth and metastatic spread of tumors.

MATERIALS AND METHODS

The effect of blocking FGF-2 synthesis by an antisense phosphorothioate oligodeoxynucleotide (PS-ODN2) was evaluated on the angiogenic activity of Caki-1 and of a cell line isolated from a renal carcinoma bone metastasis (CRBM-1990). After the transfection with PS-ODN2, FGF-2 mRNA, protein expression and angiogenic activity were evaluated.

RESULTS

In Caki-1, a not significant decrease in the released FGF-2 was observed after 72 hours. In CRBM-1990, a not significant decrease in intracellular FGF-2 protein was observed after 72 hours. Endothelial cell migration induced by the conditioned media from Caki-1 treated with PS-ODN2 for 72 hours was significantly reduced.

CONCLUSION

PS-ODN2 treatment of the established line Caki-1 induced minimal variations in FGF-2 expression, but inhibited endothelial cell migration. In CRBM-1990 cells, PS-ODN2 determined a decrease in intracellular protein without reducing the ability to induce endothelial cell migration and proliferation.

In vitro aromatic bioactivation of the weak estrogen E(2)alpha and genesis of DNA adducts

Specific A-ring hydroxylated metabolites of 17beta-estrogens are known to be endogenous pro-carcinogens, more particularly the 4-hydroxylated forms of estrogens produced by cytochrome P4501B1. In this study, we investigated whether estradiol-17alpha, the main hepatic residue of estradiol-17beta in cattle treated for anabolic purposes with estradiol containing implants, could be significantly metabolized by human cells, and whether its aromatic metabolites could induce the formation of DNA adducts as estradiol-17beta and estrone do. First, using a human kidney adenocarcinoma cell line, which expresses specifically the cytochrome P4501B1, we showed that estradiol-17alpha is bioactivated into a mixture of 2- and 4-catechol estrogens leading to the corresponding methoxyestrogens unambiguously identified by LC-APCI-MS/MS. We then demonstrated that the 2- and 4-hydroxylated derivatives of estradiol-17alpha incubated under oxidative conditions with calf thymus DNA gave stable DNA adducts and abasic sites, respectively. From these results, we can consider that human cells expressing CYP1B1-dependent hydroxylation activities metabolize estradiol-17alpha at the same magnitude as estradiol-17beta and estrone, and that in oxidative conditions, the resulting aromatic metabolites can lead to the formation of both stable and unstable DNA adducts.

Two-dimensional electrophoretic profiling of normal human kidney glomerulus proteome and construction of an extensible markup language (XML)-based database

To contribute to physiology and pathophysiology of the glomerulus of human kidney, we have launched a proteomic study of human glomerulus, and compiled a profile of proteins expressed in the glomerulus of normal human kidney by two-dimensional gel electrophoresis (2-DE) and identification with matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and/or liquid chromatography-tandem mass spectrometry (LC-MS/MS). Kidney cortices with normal appearance were obtained from patients under surgical nephrectomy due to renal tumor, and glomeruli were highly purified by a standard sieving method followed by picking-up under a phase-contrast microscope. The glomerular proteins were separated by 2-DE with 24 cm immobilized pH gradient strips in the 3-10 range in the first dimension and 26 x 20 cm sodium dodecyl sulfate polyacrylamide electrophoresis gels of 12.5% in the second dimension. Gels were silver-stained, and valid spots were processed for identification through an integrated robotic system that consisted of a spot picker, an in-gel digester, and a MALDI-TOF MS and / or a LC-MS/MS. From 2-DE gel images of glomeruli of four subjects with no apparent pathologic manifestations, a synthetic gel image of normal glomerular proteins was created. The synthetic gel image contained 1713 valid spots, of which 1559 spots were commonly observed in the respective 2-DE gels. Among the 1559 spots, 347 protein spots, representing 212 proteins, have so far been identified, and used for the construction of an extensible markup language (XML)-based database. The database is deposited on a web site (http://www.sw.nec.co.jp/bio/rd/hgldb/index.html) in a form accessible to researchers to contribute to proteomic studies of human glomerulus in health and disease.

Primary lumbosacral Wilms tumor associated with diastematomyelia and occult spinal dysraphism. A report of a rare case and a short review of literature

BACKGROUND

The occurrence of an extrarenal Wilms tumor in the lumbosacral region is an extremely uncommon condition.

CASE REPORT

We report a case of Wilms tumor in the lumbosacral region that was associated with diastematomyelia and occult spina bifida. An 18-month-old girl presented with a swelling over the lower back with a tuft of hair on it, which she had had since birth. Imaging of the spine revealed spina bifida, bony diastematomyelia, and tethered cord. Excision of the bony spur and detethering of the cord was done. After a year, she had recurrence of swelling at the same site, weakness of both lower limbs, and incontinence of bladder and bowel. Excision of the mass and bony spur and detethering of the spinal cord were done. Histopathological examination showed features of a Wilms tumor.

Renal metanephric adenoma with previously unreported cytogenetic abnormalities: case report and review of the literature

We report a case of a renal metanephric adenoma in a 10-year-old boy, in which cytogenetic analysis showed a balanced translocation, t(9;15)(p24;q24) and a balanced paracentric inversion of chromosome 12, inv(12)(q13q15). Immunohistochemically, the tumor showed diffuse reactivity for cytokeratin AE1/AE3, CAM5.2, CD57, and WT1; patchy reactivity for CD56; and focal reactivity for cytokeratin 7, epithelial membrane antigen, and CD10. Tumor cells were entirely nonreactive for alpha-methyl acyl coenzyme A racemase. Published cytogenetic data for metanephric adenomas are limited, and this is the first report of these cytogenetic abnormalities. The involvement of the chromosome region 9p24 is particularly interesting because of the recent identification of a tumor suppressor gene, KANK (kidney ankyrin repeat-containing protein), at this locus.

Ligands for peroxisome proliferator-activated receptor gamma have potent antitumor effect against human renal cell carcinoma

OBJECTIVES

To examine whether peroxisome proliferator-activated receptor gamma (PPARgamma) is expressed in human renal cell carcinoma (RCC) cells, and whether activation of PPARgamma by its ligands can have multiple antitumor effects on human RCC cells in vitro.

METHODS

We examined the expression of PPARgamma in four human RCC cell lines by reverse transcriptase-polymerase chain reaction and immunocytochemical staining. The effects of two PPARgamma ligands, pioglitazone and 15-deoxy-Delta12,14-prostaglandin J2, on cell proliferation were investigated by 3-[4,5-dimethylthiazol-2-thiazoly]-2,5-diphenyltetrazolium bromide assay. The induction of apoptosis by the ligands was examined using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling method and Annexin V assay. Furthermore, we investigated whether these ligands suppressed the production of angiogenic factors, vascular endothelial growth factor and basic fibroblast growth factor, by enzyme-linked immunosorbent assay.

RESULTS

PPARgamma and retinoid X receptor, which forms a heterodimer with PPARgamma, were expressed in all RCC cell lines. In addition, immunocytochemical studies showed expression of PPARgamma protein in the RCC cells. PPARgamma ligands inhibited the cell growth in all cells in a dose-dependent manner. These ligands also induced apoptosis. Furthermore, secretion of both vascular endothelial growth factor and basic fibroblast growth factor was inhibited by these ligands in a dose-dependent and time-dependent manner.

CONCLUSIONS

Ligands for PPARgamma have multiple antitumor effects in human RCC cells in vitro. Activation of the PPARgamma pathway may be a new strategy for treatment of patients with RCC.

Cyclooxygenase-2 and p53 expression as prognostic indicators in conventional renal cell carcinoma

The aim of this study was to investigate the relationship of cyclooxygenase (COX)-2 and p53 expression with prognosis in patients with conventional renal cell carcinoma (RCC). Formalin-fixed, paraffin-embedded tissue sections of conventional RCC from 92 patients, who had undergone radical nephrectomy, were examined for COX-2 and p53 expression by immunohistochemistry and compared with clinicopathological variables. The COX-2 expression significantly correlated only with tumor size (p=0.049), whereas the p53 expression profoundly correlated with the TNM stage (p=0.024), M stage (p=0.001), and metastasis (synchronous or metachronous; p=0.004). The COX-2 overexpression did not significantly associate with p53 positivity (p=0.821). The survival rate of patients correlated with the p53 expression (p<0.0001) but not with the COX-2 expression (p=0.7506). Multivariate analyses indicated that tumor size, M stage, and p53 expression were independent prognostic factors for cancer-specific survival. The COX-2 expression was not an independent factor. These results show that the increased expression of p53 was associated with metastasis and a worse prognosis in conventional RCC, which suggests that p53 might have played an important role in the progression of conventional RCC. The increased expression of COX-2 was associated only with tumor size, but may not be an important prognostic factor in conventional RCC. No association was observed between COX-2 overexpression and p53 positivity in conventional RCC.

Microsatellite analysis of the adenomatous polyposis coli (APC) gene and immunoexpression of beta catenin in nephroblastoma: a study including 83 cases treated with preoperative chemotherapy

AIMS

To determine whether microsatellite mutations of the adenomatous polyposis coli (APC) gene have pathological or prognostic significance in nephroblastomas and to correlate APC alterations with beta catenin immunoexpression.

METHODS

One hundred nephroblastomas were analysed, 83 of which received preoperative chemotherapy. Normal and tumour DNA was isolated using standard proteinase K digestion and phenol/chloroform extraction from paraffin wax embedded tissue. Polymerase chain reaction using four APC microsatellite markers-D5S210, D5S299, D5S82, and D5S346-was performed and the products analysed. Immunohistochemistry was performed using the LSAB kit with diaminobenzidine as chromogen. Results were correlated with clinicopathological data using the chi(2) test.

RESULTS

Allelic imbalance/loss of heterozygosity was more frequent than microsatellite instability, with 30% of cases showing allelic imbalance/ loss of heterozygosity and 16% showing microsatellite instability. Although there was a significant correlation between the results for individual markers and the clinicopathological data, the overall results do not support a prognostic role for APC in nephroblastoma. Expression of beta catenin was seen in 93% of cases. Staining was predominantly membranous, with epithelium, blastema, and stroma being immunoreactive. Cytoplasmic redistribution was seen in 58% of cases, but no nuclear staining was detected. No significant associations between beta catenin expression and the clinicopathological parameters were found. Kaplan-Meier survival plots showed that patients with loss of membranous staining and pronounced cytoplasmic staining (score, 3) had a significantly shorter survival (p = 0.04; median survival, 5.87 months).

CONCLUSION

Microsatellite analysis of APC and immunoexpression of beta catenin did not provide significant pathological or prognostic information in this cohort of nephroblastomas.

Up-regulation of the interferon gamma (IFN-gamma)-inducible chemokines IFN-inducible T-cell alpha chemoattractant and monokine induced by IFN-gamma and of their receptor CXC receptor 3 in human renal cell carcinoma

BACKGROUND

The antiangiogenic CXC chemokines interferon gamma (IFN-gamma)-inducible T-cell alpha chemoattractant (I-TAC) and monokine induced by IFN-gamma (Mig) are known as members of IFN-gamma-inducible antiangiogenic CXC chemokines. However, the expression of these chemokines in highly angiogenic tumors remains poorly understood. The authors examined expression of I-TAC, Mig, and their receptor, CXCR3, in tissue samples from patients with renal cell carcinoma (RCC).

METHODS

Twenty-one samples of untreated RCC and corresponding normal renal tissues were obtained from surgical specimens. The expression levels of I-TAC, Mig, and CXCR3 were investigated using reverse transcriptase-polymerase chain reaction (RT-PCR) analysis, real-time RT-PCR analysis, and Western blot analysis. Immunohistochemistry was carried out to clarify the localization of both chemokines and of CXCR3.

RESULTS

RT-PCR analysis showed strong expression levels of I-TAC, Mig, and CXCR3 in RCC tissues and very weak or undetectable expression in normal kidney tissues. Real-time RT-PCR analysis showed that expression levels of I-TAC, Mig, and CXCR3 in RCC tissues were 14.9 times greater, 30.3 times greater, and 9.9 times greater compared with the levels in the corresponding normal kidney tissues, respectively (P < 0.01). Western blot analysis showed up-regulation of I-TAC, Mig, and CXCR3 at the protein level. Immunofluorescence double stainings revealed that I-TAC coincided with pericytes and vascular smooth muscle cells (VSMCs) in tumor angiogenic vessels. Mig was detected in tumor endothelial cells (TECs) and in infiltrating leukocytes. In the corresponding normal kidney tissues, neither VSMCs nor endothelial cells showed positive stainings for these chemokines. CXCR3 was expressed in both tumor cells and infiltrating leukocytes.

CONCLUSIONS

The results revealed special feature of vascular mural cells and TECs in RCC. The up-regulated I-TAC and Mig, produced by tumor vessels, may interact with CXCR3 expressed in tumor cells, with possible pathophysiologic significance in RCC progression.

IL-4 inhibits proliferation of renal carcinoma cells by increasing the expression of p21WAF1 and IRF-1

Interleukin (IL)-4 inhibits proliferation of several human cancer cell lines in vitro. Although IL-4 is known to regulate proliferation of lymphocytes by modulating p27KIP1 expression, the mechanism involved in the IL-4-induced growth inhibition of nonhematopoietic cancer cells has not been fully elucidated. Previously, we reported that IL-4 suppressed proliferation of human renal cell carcinoma (RCC) cell lines in vitro. Here, we show that IL-4 inhibits cell cycle progression at the G1 phase in Caki-1 cells by increasing the expression of p21WAF1 and interferon regulatory factor (IRF)-1, and decreasing the cyclin dependent kinase (CDK) 2 activity. Up-regulation of p21WAF1 and IRF-1 expression is transcriptional, but independent of p53. The levels of p21WAF1 and IRF-1 proteins were enhanced as early as 1 h after IL-4 treatment. CDK2 activity started to decline at 4 h after IL-4 treatment, and by 24 h, was approximately 50% of the control. Neither the protein expressions of p27KIP1 and p16INK4a, nor the phosphorylation level of pRb was changed. The importance of p21WAF1 and IRF-1 in the growth inhibition induced by IL-4 was confirmed by antisense oligonucleotide transfection. Both of p21WAF1 and IRF-1 antisense oligonucleotides prevented IL-4-mediated growth inhibition by approximately 30% compared to the respective sense oligonucleotides. In summary, our study indicated that p21WAF1 and IRF-1 mediate the growth inhibitory effect of IL-4 in human RCC cells.